1. Field of the Invention
This invention relates to an apparatus to float a sample without any contact so as to carry out various types of experiments and develop new materials, and more particularly to supply of the liquid sample, and recovery of a droplet.
2. Description of the Prior Art
FIG. 22 is a sectional view of a conventional droplet floating apparatus disclosed in, for example, W. K. Rhim et al. "Electrostatic Levitators and Drop Dynamics Experiment" in Proceedings of the 7th European Symposium on Materials and Fluid Sciences in Microgravity, (1990). In the drawing, reference numerals 2a, 2b are electrodes, 5 is a nozzle, 6 is a tube to supply liquid, and 7 is a mechanism to apply an impact force to the nozzle. FIG. 23 is an enlarged view showing the nozzle and the mechanism to apply the impact force to the nozzle in FIG. 22. In the drawing, reference numeral 1 means a droplet, 1a is air, 2c is an electrode, 7a is a solenoid electromagnet core, 7b is a solenoid magnet coil, and 22 is a velvet pad attached to a distal end of the nozzle.
In such a droplet floating apparatus, the liquid supplied by the tube 6 becomes the droplet 1 at the distal end of the nozzle 5. At this time, the droplet 1 is charged by voltage applied across the electrodes 2a and 2b. The droplet 1 positioned at the distal end of the nozzle 5 is separated from the nozzle 5 by the solenoid electromagnets 7a, 7b vertically hitting a lower portion of the nozzle 5, and is thereafter floated by an electrostatic force caused by an electric field across the electrodes 2a and 2b and charge of the droplet 1.
In addition to the above application of the electric field by using the electrodes 2a and 2b, means for confining the droplet 1 in a floating space without ambient contact may include other means using a sound wave or electromagnetic repulsion disclosed in, for example, Toshio Azuma, "Observation of Vibration of Droplet by Sound Wave Floating" Parabolic Flight, (1991).
In the droplet floating apparatus as set forth above, the droplet 1 is separated from the nozzle 5 by reaction of the impact force applied to the nozzle 5. Hence, there is a problem in that a large impact force prohibits stable supply of the droplet 1 because the droplet 1 may be splashed in response to the large impact force.
Means for recovery of the droplet 1 is not disclosed in the above cited references, and it is necessary to provide any means for the recovery.